Parkinson’s Disease

Research Article

Enhancement of Executive Functions but Not Memory by Multidomain Group Cognitive Training in Patients with Parkinson’s Disease and Mild Cognitive Impairment: A Multicenter Randomized Controlled Trial

Table 4

Regression analyses: predictors for intervention success.


Model	Analysis	F-test	R² (adjusted R²)	Standardized coefficients (β) of significant predictors
Model	Analysis	F-test	R² (adjusted R²)	Baseline level	Age at baseline	Education in years	UPDRS-3 at baseline	LEDD at baseline	ApoE4 carrier

Cognitive training
Memory
ROCFT delayed recall^a	ITT	F (6, 25) = 2.688;	0.392 (0.246)	−0.506^↓	—	—	—	—	—
ROCFT delayed recall^a	PP	F (6, 22) = 3.618;	0.497 (0.359)	−0.583^↓	—	—	—	−0.373^†↓	−0.335^†↓
Executive functions
Executive functions mean score^a	ITT	F (6, 22) = 2.673;	0.422 (0.264)	−0.446^↓	—	—	—	—	—
Executive functions mean score^a	PP	n.s.	—	—	—	—	—	—	—
Semantic word fluency^a	ITT	F (6, 25) = 2.643;	0.388 (0.241)	−0.398^↓	—	—	—	0.493^↑	—
Semantic word fluency^a	PP	F (6, 23) = 2.865;	0.428 (0.278)	−0.478^↓	—	—	—	0.546^↑	—
Phonemic word fluency^a	ITT	F (6, 25) = 3.595;	0.463 (0.334)	−0.587^↓	0.405^†↑	—	−0.507^↓	0.423^↑	0.473^↑
Phonemic word fluency^a	PP	F (6, 22) = 3.660;	0.500 (0.363)	−0.592^↓	—	−0.340^†↓	−0.440^↓	0.472^↑	0.500^↑
MCST categories^a	ITT	F (6, 22) = 2.797;	0.433 (0.278)	−0.562^↓	−0.374^†↓	—	—	—	—
MCST categories^a	PP	F (6, 20) = 2.837;	0.460 (0.298)	−0.580^↓	—	—	—	—	—
Key search^a	ITT	F (6, 25) = 2.778;	0.400 (0.256)	−0.660^↓	—	—	—	—	—
Key search^a	PP	F (6, 23) = 2.651;	0.409 (0.255)	−0.660^↓	—	—	—	—	—
Working memory
Working memory mean score^a	ITT	F (6, 25) = 2.705;	0.394 (0.248)	−0.622^↓	—	—	—	—	—
Working memory mean score^a	PP	F (6, 23) = 2.670;	0.411 (0.257)	−0.633^↓	—	—	—	—	—
Digit span backward (WAIS)^a	ITT	F (6, 25) = 5.311;	0.560 (0.455)	−0.729^↓	—	—	—	—	—
Digit span backward (WAIS)^a	PP	F (6, 23) = 5.700;	0.598 (0.493)	−0.744^↓	—	—	—	—	—
Visuocognition
Visuocognition mean score^a	ITT	F (6, 25) = 5.052;	0.548 (0.440)	−0.548^↓	0.334^†↑	—	—	—	—
Visuocognition mean score^a	PP	F (6, 23) = 4.770;	0.554 (0.438)	−0.552^↓	—	—	—	—	—
ROCFT figure copy^a	ITT	F (6, 25) = 3.460;	0.454 (0.323)	−0.515^↓	—	—	—	—	—
ROCFT figure copy^a	PP	F (6, 23) = 3.296;	0.462 (0.322)	−0.537^↓	—	—	—	—	—
Benton judgment of line orientation^a	ITT	F (6, 25) = 5.049;	0.548 (0.439)	−0.722^↓
Benton judgment of line orientation^a	PP	F (6, 23) = 5.009;	0.567 (0.453)	−0.726^↓	—	—	—	—	—
Language
Language mean score^a	ITT	F (6, 25) = 3.012;	0.420 (0.280)	−0.565^↓	—	—	−0.441^↓	—	0.463^↑
Language mean score^a	PP	F (6, 23) = 2.786;	0.421 (0.270)	−0.555^↓	—	—	−0.392^↓	—	0.407^†↑
Speech comprehension (ACL)^a	ITT	F (6, 25) = 3.842;	0.480 (0.355)	−0.642^↓	—	—	—	—	—
Speech comprehension (ACL)^a	PP	F (6, 23) = 3.672;	0.489 (0.356)	−0.655^↓	—	—	—	—	—
Noncognitive outcomes
BDI-II^b	ITT	F (6, 25) = 2.858;	0.407 (0.264)	−0.473^↑	−0.365^†↑	—	—	—	—
BDI-II^b	PP	F (6, 23) = 2.724;	0.415 (0.263)	−0.489^↑	—	—	—	—	—
UPDRS-III^b	ITT	F (5, 26) = 3.281;	0.387 (0.269)	−0.328^†↑	—	0.403^↓	—	—	—
UPDRS-III^b	PP	F (5, 24) = 4.583;	0.488 (0.382)	−0.372^↑	—	0.467^↓	—	−0.376^†↑	—

Control group
Memory
CVLT total score trials 1–5^a	ITT	F (6, 20) = 2.978;	0.472 (0.313)	−0.702^↓	−0.456^†↓	—	—	—	—
CVLT total score trials 1–5^a	PP	F (6, 19) = 3.051;	0.491 (0.330)	−0.690^↓	−0.429^†↓	—	—	—	—
CVLT long delay free recall II^a	ITT	F (6, 20) = 3.219;	0.491 (0.339)	−0.362^↓	−0.776^↓	−0.637^↓	—	—	—
CVLT long delay free recall II^a	PP	F (6, 19) = 3.042;	0.490 (0.329)	−0.346^†↓	−0.777^↓	−0.599^↓	—	—	—
ROCFT delayed recall^a	ITT	F (6, 21) = 4.872;	0.582 (0.462)	−0.527^↓	0.462^↑	—	—	—	—
ROCFT delayed recall^a	PP	F 6, 20) = 4.640;	0.582 (0.456)	−0.523^↓	0.459^↑	—	—	—	—
Executive functions
Key search^a	ITT	F (6, 21) = 4.075;	0.538 (0.406)	−0.780^↓	—	—	—	—	—
Key search^a	PP	F (6, 20) = 3.942;	0.542 (0.404)	−0.785^↓	—	—	—	—	—
Visuocognition
Visuocognition mean score^a	ITT	F (6, 21) = 2.972;	0.459 (0.305)	−0.654^↓	—	—	—	—	—
Visuocognition mean score^a	PP	F (6, 20) = 3.285;	0.496 (0.345)	−0.667^↓	—	—	—	—	—
ROCFT figure copy^a	ITT	F (6, 21) = 5.361;	0.605 (0.492)	−0.796^↓	—	—	—	—	—
ROCFT figure copy^a	PP	F (6, 20) = 5.638;	0.628 (0.512)	−0.802^↓	—	—	—	—	—
Language
Language mean score^a	ITT	F (6, 21) = 9.890;	0.739 (0.664)	−0.847^↓	—	—	—	—	—
Language mean score^a	PP	F (6, 19) = 9.417;	0.748 (0.669)	−0.856^↓	—	—	—	—	—
Boston naming test^a	ITT	F (6, 21) = 6.582;	0.653 (0.554)	−0.678^↓	—	—	—	—	—
Boston naming test^a	PP	F (6, 20) = 6.563;	0.663 (0.562)	−0.619^↓	—	—	—	—	—
Speech comprehension (ACL)^a	ITT	F (6, 21) = 25.963;	0.881 (0.847)	−0.900^↓	—	—	—	−0.196^↓	—
Speech comprehension (ACL)^a	PP	F (6, 19) = 23.387;	0.881 (0.843)	−0.899^↓	—	—	—	−0.187^†↓	—

Dependent variables are defined as Δposttest − pretest; only those regression models that reached statistical significance at are presented; for each significant regression model, standardized regression coefficients are reported for predictors that have reached statistical significance only; ^†; ; ; . ACL, Aphasia Check List; ApoE, apolipoprotein E; BDI, Beck Depression Inventory; CVLT, California Verbal Learning Test; ITT, intention-to-treat analysis; LEDD, levodopa equivalent daily dose; MCST, Modified Wisconsin Card Sorting Test; PP, per-protocol analysis; ROCFT, Rey–Osterrieth Complex Figure Test; UPDRS, Unified Parkinson’s Disease Rating Scale; WAIS, Wechsler Adult Intelligence Scale. ^aHigher change scores indicate higher training gains; ^blower change scores indicate higher training gains. ^↓Lower predictor level predicts higher training gains. ^↑Higher predictor level predicts higher training gains.